The phenomenon of Shadow IT is not particularly popular among IT folks. They typically feel, with some justification, that users are simple-minded bottom-feeders with no sense of how their individual needs fit into the company's larger technology efforts.
That may be true as far as it goes, but that view is ultimately just as myopic as what IT ascribes to users, and it fundamentally misunderstands technology's role in the enterprise.
See also: 6 ways Shadow IT can actually help IT
To the extent that IT is providing technology services to the company, it exists only to serve the needs of the company's users, and the policies it sets and enforces must be tailored to fit those needs. If those users are rejecting IT's official offerings in favor of unauthorized shadow IT alternatives, that's likely because IT has failed to provide them what they need—and/or failed to convince them that those official offerings really do fit their needs.
They key point here is that it's ultimately the business users, not IT, who get to decide exactly what does and does not fit their needs. It's up to IT to persuade—not force—the business to stick to the company-approved solutions. IT needs to understand that business users are judged on their ability to succeed in the market, not on how good of a corporate citizen they are in terms of doing what IT tells them to do.
That's always been true, of course, but IT was long sheltered from the effects of that reality by the fact that users couldn't easily obtain even remotely viable alternative solutions, and were pretty much stuck with whatever IT chose to give them.
With the consumerization of IT, however, that's emphatically no longer the case. From the user perspective, many shadow IT options now appear vastly better, faster, cheaper, easier to learn, easier to use, and easier to implement than the company-provided solutions. They may or may not be as secure or easy to manage at scale, but most users—again, with some justification—don't see that as their problem.
In this scenario, IT must figure out how to deliver vetted solutions that users will actually choose to use, either because the products and solutions are so awesome or because IT is able to convince users that the things IT cares about are so dang important that users should accept a second-class experience in order to stick with them.
The first approach is increasingly possible if IT is on top of its game. The second one is typically hopeless.
Either way, though, if IT fails to convince users to use the official products and services, its role will quickly devolve into cleaning up the messes caused by that failure. In a classic Catch-22, the security and manageability issues mentioned above are the responsibility of the IT department, not the business users.
Ironically, perhaps, that may be the role IT is evolving into: monitoring, managing, securing, and integrating the solutions chosen by business users (ideally, but not necessarily, with input and leadership from IT).
IT as a creative force
If that doesn't sound like much fun for IT folks, there is another path. While IT usually can't escape responsibility for the company's technology infrastructure, the real opportunity is working with the business to create new digital experiences for customers. That can mean everything from developing standalone mobile apps to leveraging software to improving existing products and services to drive revenue and growth.
Sure, you may still struggle to cope with shadow IT, but at least that won't be all you're doing.